Joystick

Two axes in one gesture. Drag the handle and the device receives where it is — left/right and up/down together — which is what a rover, a drone or a pan-tilt camera needs to move smoothly.

What it does

The handle position is written as one text value, x,y, each axis from -1.00 to 1.00. Both axes always travel together, in one message: the device never sees an X without its Y, so a direction is never wrong for the length of a round trip. On release the joystick either springs back to center (sends 0,0) or stays put.

When to use it

• Driving — a differential rover: x steers, y sets the speed.
• Aiming — a pan-tilt camera, a laser, a servo pair.
• Anything with two degrees of freedom at once.

Set it up

1. Declare a Text signal — A joystick sends both axes in one text value, so it needs a Text signal. Tap the device icon, then Declare a signal, and choose the type Text.
2. Place it — Back on the dashboard, tap + and choose Joystick under Controllers. Six columns square is a comfortable size.
3. Wire it to the signal — Tap the joystick, open the Data tab, tap + Add a target and pick the Text signal.
4. Choose what happens on release — In the same tab, under On release, keep Back to center for anything that moves — the handle springs back and the device receives 0,0. Close the settings, tap ▶, and drag.

Settings

Tap the widget in edit mode: the sheet opens with a live preview at the top, then two tabs — Data for what it reads or writes, Appearance for how it looks.

Data — what it writes

Targets

What each gesture sends

On release

Appearance — how it looks

Title

Colors

States

• Dragging — a stream of x,y, paced. Released — 0,0, or the last position, depending on On release.
• Device offline — a joystick is a gesture, nothing is replayed.

Arduino device code

The address is all the device knows — I2 here; use the one the app gave your signal. In the sketch, the block receives both axes, already split:

IJoystick(I2, float x, float y) { … };

Complete sketch — Cloud

Paste it into the Arduino IDE, put your Wi-Fi and the token the app gave you, upload.

#include <InstantIoT.h>

const char* WIFI_SSID    = "MyWiFi";
const char* WIFI_PASS    = "MyPassword";
const char* DEVICE_TOKEN = "PASTE_TOKEN_HERE";

IJoystick(I2, float x, float y) {   // x: -1 left … 1 right · y: -1 back … 1 forward
    drive(x, y);
};

void setup() {
    Serial.begin(115200);
    InstantIoT.begin(WiFiLink(WIFI_SSID, WIFI_PASS), Cloud(DEVICE_TOKEN));
}

void loop() {
    InstantIoT.loop();
}

Other connections

The widget block never changes. Only the begin() line says how the device reaches the app:

Direct needs no token: the phone is at the other end of the wire. See Connect for TLS, timeouts and what to do when it does not connect.

ISignal does the same job — and survives a restart. ISignal(I2, const char* v) runs with exactly the same value as IJoystick(I2, float x, float y): the widget block is the readable form, ISignal the generic one, and you can use either. The difference shows when the device reconnects: with Restore after a restart on the signal, the Cloud sends the last value again and only the ISignal block runs — a joystick is a gesture, nothing is replayed — and IJoystick already splits the text into x and y for you. See One block for everything.

Notes

• Use Back to center for anything that moves. A rover that keeps driving after the finger lifts is a rover in the wall.
• Keep drive() fast — set two PWM values and return. The device receives a stream while you drag.
• Two joysticks (drive + camera) need two Text signals.

Next

→ Direction Pad — steps instead of a continuous position → Horizontal Slider — one axis